Note: Descriptions are shown in the official language in which they were submitted.
CA 02036828 2000-02-07
TITLE OF THE INVENTION
Developing device
BACKGROUND OF THE INVENTION
1. Field of the invention
The present invention relates to a developing device
provided in an electrophotographic recorder.
2. Description of the related Art
An electrophotographic recorder used as a copying
machine, a facsimile, a laser printer, etc has a charger,
an exposure device, a developing device, a transfer
device, and a fixing device sequentially arranged around a
photosensitive drum in its rotating direction.
In the operation of the recorder, the photosensitive
drum is caused to rotate, the exposure device exposes the
charged surface of the rotating drum to form a latent
image, the developing device develops the latent image on
the surface of the rotating drum with toner to form a
toner image, the transfer device transfers the toner image
from the surface of the drum to a recording paper, and the
fixing device fixes the toner image on the recording
paper.
The developing device provided in the
electrophotographic recorder stores toner in its device
body and supplies toner from the device body to the
surface of the photosensitive drum.
When the toner in the device body is exhausted, toner
is supplied into the device body.
In one method to supply toner into the device body of
the developing device, an exchangeable toner cartridge is
used.
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The toner discharge port of the toner cartridge is
covered with a strip-shaped sheet.
When the toner cartridge is mounted in the device
body of the developing device, the flange of the toner
cartridge is inserted to the guide rails of the device
body, and the toner cartridge is slid along the guide
rails of the device body till the front flange of the
toner cartridge contacts and fits into the stopper of the
device body.
The toner discharge port of the toner cartridge then
coincides with the toner reception port of the device
body.
The externally projecting end of the strip-shaped
sheet is pulled by the operator to separate the strip-
shaped sheet from the toner cartridge, so that the toner
discharge port is opened, and the toner stored in the
toner cartridge is discharged from the opened toner
discharge port into the device body through the ports.
When the toner in the device body 8 of the developing
device is exhausted, the front edge of a cartridge cover
16' is connected to the edge 15 of the device body 8, and
the toner cartridge 19' is slid along the guide rails 17
of the toner cover 16' and the guide rails 17 of the
device body 12, till the front flange of the toner
cartridge 19' is located at the stopper piece 18, as shown
in Fig. 11.
However the conventional cartridge cover has the
following problems.
The cartridge cover of the conventional developing
device is made from a material which is flexible, for
example vinyl chloride.
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Thus the edge of the cartridge cover 16' is sometimes
caught on the edge of the toner discharge port 20, when
the toner cartridge 19' is slid from the upper portion of
the device body 8 to the base 16a of the cartridge cover
16', and the base 16a of the cartridge cover 16' is bent
inward toward the toner cartridge 19' is shown in Fig.
12 (b) .
As shown in Fig. 13, the edge 16z of the conventional
cartridge cover 16' is vertical to the direction in which
the toner cartridge is removed
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from the device body to the cartridge cover.
And as shown in Fi.g. 14, the edge 19z of the
conventional toner cartridge 19' is vertical to the
direction in which the toner cartridge is removed from the
device body to the cartridge cover.
When the base 16a of the cartridge cover 16' is bent
inward toward the toner cartridge 19', the edge 16z of the
cartridge cover 16' is caught on the edge 19z of the toner
discharge port 20, and the base 16a of the cartridge
cover 16' does:n't cover the toner discharge port 20
perfectly.
The toner resting in the toner cartridge 19' is then
leaked out of 'the gap between the toner cartridge 19' and
the device body 8.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a
developing device in which a cartridge cover can cover a
toner discharge port of a toner cartridge perfectly,
without toner :Leaking out of the gap between the toner
cartridge and i:he device body when the toner cartridge is
dismounted from the device body.
In accordancE~ with one aspect of the present invention
there is provided a developing device for supplying toner
to a photosensitive member, comprising: a device body
having a toner reception port which supplies toner stored
therein to the photosensitive member; a toner cartridge
detachably mounted on the device body in coincidence with
the toner reception port, having a toner discharge port
opposed to the toner reception port, which supplies toner
stored therein to the device body through the ports; a
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toner cartridge cover having a base for covering the toner
discharge port, side edges for interfacing with the toner
cartridge, a front edge for engaging the device body and
first contacting the toner cartridge, and a rear edge; and
wherein said front edge is shaped to prevent interference
with an edge of the toner discharge port when the toner
cartridge is slid over the toner cartridge cover, said
front edge in -the shape of one of a V protruding inward
toward the rear edge of the toner cartridge cover, a U
protruding inward toward the rear edge of the toner
cartridge cover or a slant to the edge of the toner
discharge port.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are incorporated in and
constitute a part of the specification, illustrate a
presently preferred embodiment of the invention and,
together with t:he general description given above and the
detailed descr_Lption of the preferred embodiment given
below, serve to explain the principles of the invention.
Fig. 1 to Fic~. 10 show an embodiment of a developing
device according to the present invention.
Fig. 1 is a ;side view showing a facsimile machine using
the developing device of the present invention.
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Fig. 2 is a perspective view of the device body of
the developing device.
Fig. 3 (a) to Fig. 5 (a) are top views of a cartridge
cover of the developing device.
Fig. 3 (b) to Fig. 5 (b) are slant views of a
cartridge cover of the developing device.
Fig. 6 (a) , (b) and Fig. 7 (a) , (b) are perspective
views of a toner cartridge of the developing device.
Fig. 6 (b) and Fig. 7 (b) shows the toner cartridge
as shown in Fig. 6 (a) and Fig. 7 (a) upside-downed.
Fig. 8 to Fig. 10 are perspective views showing the
use of the toner cover connected to the device body of the
developing device.
Figs. 11-14 are perspective views showing the use of
the toner cover on the conventional device body of the
developing device.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Fig. 1 shows a facsimile, one embodiment of an
electrophotographic device using the developing device of
the present invention.
Recording paper P is the medium on which is recorded
pictures and characters.
Cassette 1 is provided to accumulate the recording
paper P in its body.
Supplying Roller 2 picks up the recording paper P
from the cassette 1.
Guide 3 decides the route of the recording paper P.
Sending Roller 5 sends the recording paper P along
the guide 3.
Dividing Roller 4 divides one sheet of recording
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paper from several sheets of recording paper P.
Photosensitive drum 6 records the picture information
when the surface of its body is exposed to the light which
contains the picture information.
Developing device 8 supplies the toner to the
photosensitive drum 6.
Exposure device 9 exposes the light having the
picture information to the photosensitive drum 6.
The developing device 8 supplies the toner to the
surface of the photosensitive drum 6, as explained above.
Fixing device 7 fixes the toner image on the
recording paper P.
Transfer device 10 transfers the toner image from the
surface of the photosensitive drum 6 to the recording
paper P.
Stacker 11 stacks the recording paper P which is sent
from the photosensitive drum 6.
In the operation of recording the image, the
recording paper P accumulated in the cassette 1 is picked
up by the supplying roller 2, first of all.
The recording paper P is separated from other
recording paper, and is sent to the photosensitive drum 6
along the guide 3 by the sending roller 5.
The recording paper P records the toner image on the
surface by the photosensitive drum 6, which is exposed to
light by the exposure device 9, and is supplied toner by
the developing device 8.
The image is transferred to the recording paper P by
the transfer device 10, and is fixed by the fixing
device 7.
Finally, the recording paper P is stacked on the
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stacker 11.
The developing device 8 of the present invention
consists of the device body, the toner cartridge 19', and
the cartridge cover 16.
And the developing device 8 of the present invention
consists of the device body, the toner cartridge 19, and
the cartridge cover 16'.
The toner cartridge 19' and the cartridge cover 16'
are conventional.
Fig. 2 shows the device body 8 of the developing
device.
The device body 8 has a toner reception port 13 which
is formed at the center of the upper plate of the case.
A pair of guide rails 12 are formed at the
longitudinal side edges of the upper plate along both
longitudinal sides of the toner reception port 13.
The guide rails 12 support the toner cartridge
slidably.
A toner cartridge mounting port is defined by the
surface of the upper plate of the case, the inner side
surface of the guide rails and a stopper 14 at the end of
the guide rails 12, which is formed to bridge over both
the guide rails 12.
Fig. 3 to Fig. 5 are perspective views of a cartridge
cover.
The cartridge cover 16 has a base 16a having
substantially the same dimension as the lower plate of the
cartridge.
Guide rails 17 are located at both longitudinal side
edges on the base 16a.
The guide rails 17 are formed in a strip-shape for
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laterally retaining flanges formed at both side edges of
the toner cartridge.
Each guide rail 17 extends in the longitudinal
direction and has an U-shaped cross-section, so that the
outer side surface and the upper and lower surfaces
thereof can slidably guide each flange of the toner
cartridge.
A releasing member 16c is composed of an elastic
piece extending externally rearwardly from one end of one
guide rail.
A stopper piece 18 is located at the rear end of base
16a.
In this embodiment, the base 16a, the guide rail 17,
and the stopper piece 18, are integrally formed of
synthetic resin sheet, for example vinyl chloride sheet.
The front edge 16b of the cartridge cover as shown in
Fig. 3 is shaped to be a V, and thus can avoid the force
from the edge of the toner cartridge when it is slid over
the cartridge.
The front edge 16d of the cartridge cover as shown in
Fig. 4 is shaped to be slanted to the direction in which
the toner cartridge is slid.
The front edge 16e of the cartridge cover as shown in
Fig. 5 is shaped to be a U.
Fig. 6 (a) and Fig. 7 (a) shows a toner cartridge,
according to another embodiment of this invention, and
Fig. 6 (b) and Fig. 7 (b) shows the toner cartridge as
shown in Fig. 6 (a) and Fig. 7 (a) upside-downed, as is
evident from the drawings, a conventional cartridge cover
may be used if the opening of the toner cartridge is
designed as a V, a U, or slant shape as shown in Fig. 6
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and Fig. 7.
Toner cartridges 19 store the toner to be supplied
into the device body 8 of the developing device.
A toner cartridge 19 has a toner discharge port 20
for discharging the stored toner at a lower surface to its
body.
The toner cartridge 19 has a flange 21 around the
toner discharge port 20.
The flange 21 is composed of a front flange for being
inserted to the guide rail of the device body in case the
toner cartridge 19 is mounted in the device body 9, two
side flanges for being slid to the cartridge cover,
another end flange with means for fastening the toner
cartridge 21 into the device body 8.
The toner discharge port 20 of the toner cartridge
19, before being used, is covered with the strip-shaped
sheet.
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The front edge or the end edge of the toner discharge
port 20 is shaped to be slanted in the direction that the
toner cartridge 19 is slid as shown in the Fig. 6, or is
shaped to be V as shown in Fig. 7.
When the toner cartridge 19 is mounted in the device
body 8 of the developing device, the side flange of the
toner cartridge 19 is first inserted into the guide
rail 12 of the device body 8, and the toner cartridge 19
is slid to the stopper edge 14 of the device body 8.
When the toner cartridge 19 is stopped sliding by the
stopper edge 14 of the device body 8, the toner discharge
port 20 of the toner cartridge 19 is opposed to the toner
reception port 13 of the device body 8.
The strip-like sheet is removed from the toner discharge
port 20, and then the toner stored in the toner
cartridge 19 i:~ discharged to the inside of the device
body 8 through the toner discharge port 20 of the toner
cartridge 19 and the toner reception port 13 of the device
body 8.
The toner cartridge, is then removed from the device
body 8.
Figs. 8 to 10 show a toner cover 16 which is used for
removing the toner cartridge from the device body 8.
The front edge 16b of the toner cover 16 as shown in
Fig. 3, is connected to the edge 15 of the device body 8,
as shown in Fiq. 8.
The toner cartridge 16 is moved from the upper end of
the device body 8 to the base 16a of the cartridge
cover 16 along the guide rails 17 of the device body 8 and
the cartridge cover :L6, until the front flange of the
toner cartridge' 19 is stopped sliding by stopper piece 18
of the toner cover 16, as shown in Fig. 8.
Then the base 16a of the cartridge cover 16 is
covered with the toner discharge port 20 of the
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toner cartridge 19', as shown in Fig. 10.
The guide rails 17 of the cartridge cover 16 support
the side flange of the toner cartridge 19'.
If the base 16a of the cartridge cover 16 is bent to
the inside of the toner cartridge 19' in the toner
cartridge removal, the edge 16b of the cartridge cover 16
isn't caught in the edge of the toner discharge port 20.
The front edge 16b of the cartridge cover 16 is
shaped to be a V.
This shape is one that can avoid being given the
force from the edge of the toner reception port 13, when
toner cartridge 19 is slid.
A U and a slant to the edge of the toner discharge
port which the front edge 16d, 16e of the cartridge cover
16 are shaped to be as shown in Fig. 4 and Fig. 5, also
are the shape that can prevent being given the force from
the edge of the toner discharge port 20, when toner
cartridge 19 is slid.
The idea illustrated in the above developing device
may be adjusted to a developing device which has a
conventional cartridge cover 16' and a toner cartridge 19
made as shown in Fig. 6 or Fig. 7.
The edge 19b, 19c of the toner reception port 20 may
be shaped to avoid being given the force from the front
edge 16z of the cartridge cover 16', if the toner
cartridge 19 is slid, so that the edge of the toner
discharge port 20 is gotten over the front edge 16z of the
cartridge cover 16'.
The edge 16z of the cartridge cover 16' isn't caught
in the edge 19b, 19c of the toner discharge port 20.
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